Spring tooth harrow



May 9, 1939. J. l. HOKE SPRING TOOTH HARROW Filed Jan. 28', 1937 INVENTOR. fa/w l'. Home,

ATTORNEY.

Patented May 9, 1,939

STATES PATENT FFCE 14 Claims.

This invention relates to a cultivating device known broadly as a spring tooth harrow cultivator.

The chief object of this invention is to fabricate a spring tooth harrow of identical units and associate the same together in predetermined relationship so that they accommodate themselves to the surface of the ground being cultivated and maintain linear travel.

I'he chief feature of the invention consists in forming the spring tooth harrow structure such that the several units thereof are relatively independent of each other but tractively associated with a towing member in such a manner that each unit has predetermined linear directional movement, 'said movement being of non-interfering character and said units further being characterized by a relative balancing of the spring teeth whereby substantially the entire Width of the strip being cultivated in each passage of the agricultural device is fully and completely cultivated between units to the same extent it is cultivated within the width of each unit.

Another feature of the invention consists in the specific type of tractive connection between the unit and the common towing member.

Another feature of the invention consists in the formation of each unit such that a minimum number of different parts are required and in CID the formation of the entire agriculture device a minimum number of different parts are required.

The full nature of the invention will be understood from the accompanying drawing and the following description and claims:

In the drawing, Fig. l is a top plan view of spring tooth harrow structure embodying the invention.

-lElig. 2 is a side elevational view of the same.

Fig. 3 is an enlarged top plan view of one ofthe unit connections.

Fig. 4 is a side elevational view thereof.

In the drawing I indicates a channel member to which is suitably secured the brackets II of which there are two and each has an upwardly and forwardly directed tongue I2 apertured at I3 to receive the eye It of a pull rod I5. The adjacent eyes IB at the other ends of the two pull rods `l5 are associated with the ring i'lto which the tractive power is connected. This may be a tractor or a team.

Herein `the invention is shown as including three units and since the same preferably for production purposes are made identical and are herein so illustrated, a description of one unit will suffice for all.

A substantially rectangular frame with an open rear end, in effect a U-shapecl arrangement, in-

I cludes-the midportion VI8 and'thetwo side or arm of one side only portions i9. The same may be fabricated from a single piece of angle iron. If desired, the two side portions i9 may have secured to the underface thereof, ground engaging shoes 20 or wearing strips whenever desired.

As shown clearly in Fig. 2, the immediate forward portion of the U-shaped frame is tilted upwardly and slightly, as indicated at 2I. Adjacent the junction of the horizontal and slightly upturned portions of the two side portions I9 and suitably secured to each, is a shaft bearing 2,2, the axis of the opposite shaft bearings being in alignment.

Rearwardly thereof and at a suitable distance is another pair of shaft bearings 23 andY rearwardly thereof is another shaft bearing structure 2li. As shown clearly in Fig. 2, the shaft bearings 22 and 23 are substantialy identical Aand the same may be secured as at 22a and 23a to the bottom flange of the arm I9. The shaft bearing structure 24, however, differs therefrom and is herein shown secured vto the outer side of the side flange of the angle iron I9 as at 24a. All bearings may be so mounted. Mounted in the bearings 22 is the shaft 25. Mounted in the bearings 23 is the shaft 2li and vmounted in the bearings 2i is thevshaft 2l.

The shaft `25 may be provided with two collars 28 suitably secured as at 29 for retaining the shaft in the bearings and against axial displacement. Similarly, shafts 26 and 2l' may be provided with retaining collars 28 and suitably secured thereto Ias at 20. In certain instances a bolt may constitute the shaft and the bolt head or nut thereon may replace the shaft collars. Herein the shafts 2S and 26 include laterally projecting portions with reference to the arms I9. Shaft v25 includes alright hand extension 25a and shaft 26 includes a left hand extension 26a.

The spring teeth of the harrow, as shown in Fig. 2, are herein illustrated broadly as of the shovel spring tooth type. Any other type, may be substituted for that disclosed herein Without departing from the invention. Each tooth includes a main andcurved body portion 30 having the ground engaging point 3l at one end and an arcuate anchoring portion 32 at the opposite end. A suitable anchorage 33 `is adapted to secure each tooth to its supporting shaft.

As shown in Fig. 1 between the arms `I9 of the frame unit, two spring teeth are secured to the shaft and on the right hand projecting end 25a thereof is secured a similar spring tooth. `On shaft 26 between the two arms iS of the unit frame are secured two spring teeth 30 and on the lefthand projecting end 26a of the shaft 26 isk secured another spring tooth 30. In linear alignment with each of the arm portions I9and on shaft ,2l is secured spring teeth 30. Midway therebetween is secured an intermediate spring tooth. The several spring teeth on the several shafts are offset or staggered relative to each other and a distance apart equal to the distance between the adjacent teeth of the same shaft divided by the number of shafts.` In other words, there are three shafts herein illustrated, each succeeding tooth on successive shafts from front to rear is offset one-third of the distance between the two adjacent teeth on the forward shaft.

With respect to each of the spring teeth positioned on the frame projecting ends of the shaft, the same is positioned the same distance from the adjacent tooth on that shaft as the adjacent teeth on each shaft are positioned apart.

From the foregoing, therefore, it will be noted that two of the rearward teeth on the rearward shaft are in linear alignment with the sides i9 and the intermediate tooth is midway therebe tween. This serves to insure linear travel of the unit.

It will also be observed that the projecting teeth, having reference to the teeth mounted on the projecting portion of the respective shafts, are on opposite sides of the unit further insuring a balancing of the structure.

It will furthermore be observed-see Fig. 1- that with respect to adjacent units that the adjacent projecting teeth are offset relative to each other and herein the spacing between units is such that the offsetting between the adjacent projecting teeth is the same as the offsetting between the adjacent teeth on adjacent shafts. This insures non-interference between units and since each unit is constrained to linear travel, linear travel of the entire structure will result therefrom.

Referring more especially to Figs. l and 2, it will be noted that to shaft 25 is secured an arm 40 as at 4| and to shaft 26 is secured an arm 152 as at 43.

A lever arm 44 is rigidly secured as at 45 to the shaft 21. The lever arm 44 is pivoted as at 46 to a rack plate M, the same having an arcuate rack 48 operatively associated with the lever M. Rigid with the plate 4l or integral therewith is the bar portion 49 pivoted at 5d to the arm 42 and also pivoted at 5l to the arm fl. By means of this mechanism, the teeth can be tilted upwardly so as to be free of the ground or can be tilted downwardly into the position to secure the desired depth of cultivation or penetration and simultaneously.

From an inspection of Fig. 1, it will be apparent that each of the units is identical, and the arrangement of the respective parts thereof is such there is a cooperative relationship whereby non-interference between units in operation is obtained.

The channel shaped towing member l0 may be a tube. To it there is secured a plurality, and herein a pair of anchorages 60 as at GI and providing eye portions 62. The spacing between each pair of eye portions not necessarily but is preferably slightly greater than the overall width of each unit frame. The spacing between adjacent pairs of anchorages of adjacent units is such that the predetermined spacing between the adjacent offset cooperating teeth on adjacent units is effected. From the foregoing it will be understood that each forward end or corner of the unit is attached to an adjacent anchorage Sil.

One form of connection includes a twisted link structure having the eye portion 63 and the elongated loop portion 64. Immediately adjacent the transverse portion I8 of the U-frame and projecting outwardly from the side ange of the arm portion I9 thereof, is a rigidly anchored member 64a in the form of a rivet, or the like, which secures a headed anchoring member, including the link bearing portion 65, and the head p0rtion 66, the latter being' relieved or cut away as at 6l. The minimum width of the head portion E6 is such that it may readily pass through the elongated loop portion 64 and when the connection is in tension, the rear end of the loop portion indicated by the numeral 68, engages the bearing portion 65 of the anchorage.

Another form of connection may be a link bar or a plurality of chain links.

If desired, the frame anchor member may be rotatable for connection purposes and then locked in retaining position.

The eye portion 63 is pivotally associated with the rearwardly projecting portion 62 of the anchorage 50. Thus, as will be apparent, in Figs. 1 and 2, the link connection 63-64 has a pivotal connection to the towing member ID, the axis being perpendicular, and a pivotal connection with the frame unit, the axis being horizontal. It will also be apparent this type of connection is of the readily attachable and detachable type.

The foregoing structure permits the units to be readily detached, stacked and stored or shipped in the knock-down. The foregoing also clearly illustrates and describes a construction, whereby a minimum number of different parts are required. These different parts briey are as follows:

The ring l1, the pull rod l5, the anchorage Il, the towing member I0, the anchorage 6B, the link 63-66 and a plurality of identical units, each unit including a U-shaped frame, identical shafts 25 and 26, because the shaft 25 upon reversal may be positioned as shaft Z6 is positioned, the several collars 28, the several spring teeth, one connecting bar and arcuate rack lll- 49, two identical bar connections liti and 42, a lever 44 and mechanism associated therewith for securing lever i4 in predetermined position relative to the arcuate rack 8, the substantially identical shaft mountings 22 and 23 and the rear shaft mountings 24.

It is also to be observed that whenever relative movement is desired between the parts of a unit, the U-shaped frame may be articulated and such articulation would be included preferably at or near the junction of the arms I9 with the transverse portion I8.

From the foregoing, it is to be understood that the towing member can be of any desired length and to the same is detachably secured the desired number of units. For production purposes, the units may be made of a plurality of sizes. The result therefore, is that substantially any desired spring tooth harrow structure can be readily assembled to fulfill the particular needs of the purchaser.

Also, although the units are shown as including three teeth to the shaft, making a nine tooth unit, a greater number of teeth, or shafts may be incorporated.

Also, as hereinbefore suggested, the midportion of the U-shaped frame may be articulated medianally or the arms thereof may be hingedly connected to the ends of midportion I8 whenever desired. The latter formation permits the same arms to be used in 9 and l2 tooth units, only the length of portion I3 and the tooth supporting shafts changing.

From the foregoing it is observed that the clearance between teeth is sumcient to prevent clogging due to sod, trash, clods or stones. Merely for illustration, the spacing between teeth on the same shaft may be l2 and the spacing between adjacent teeth on adjacent shafts may be 4".

While the invention has been described in great detail in the foregoing description, the same and specific illustration thereof are to be considered illustrative and not restrictive in character. Various modifications of the invention herein broadly disclosed will readily suggest themselves to persons skilled in this art and such modifications are all considered to be within the broad scope of this invention, reference being had to the appended claims.

The invention claimed iszl. A spring tooth harrow structure including an elongated transverse towing member, means for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retaining the connecting means in selected position corresponding to the tilted position desired, and a plurality of harrow spring teeth rigid with each shaft, each shaft including a plurality of teeth between the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts being offset for tooth staggering, and a 'spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as between the other teeth thereon.

2. A spring tooth harrow structure including an elongated transverse towing membermeans for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally -supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retaining the connecting means in selected position corresponding to the tilted position desired, and a plurality of harrow spring teeth rigid with each shaft, each shaft including a plurality of teeth between the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts `being offset a division of said spacing equal to the reciprocal of the number of shafts for tooth staggering, and a spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as between the other teeth thereon.

3. A spring tooth harrow structure including an elongated transverse towing member, means for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retainingthe connecting means in selected position corresponding to the tilted position desired, and

a plurality of lharrow spring teeth rigid with each shaft, each shaft including a plurality of teeth between the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts being offset for tooth staggering, and a spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as between the other teeth thereon, successive shafts projecting oppositely from the frame.

4. A spring tooth harrow structure including an elongated transverse towing member, means for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retaining the connecting means in selected position corresponding to the tilted position desired, and a plurality of harrow spring teeth rigid with each shaft, each shaft including a plurality of teeth Abetween the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts being offset a division of said spacing equal to the reciprocal of the number of shafts for tooth staggering, and a spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as be tween the other teeth thereon, successive shafts projecting oppositely from the frame.

5. A spring tooth harrow structure including an elongated transverse towing member, means for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retaining the connecting means in selected position corresponding to the tilted position desired, rand a plurality of harrow spring teeth rigid with each shaft, 'each shaft including a plurality of teeth between the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts being voffset for tooth staggering, and a spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as between the other teeth thereon, the spacing between adjacent frames being the same as the spacing between the teeth on the same shaft.

6. A spring 'tooth harrow structure including an elongated transverse towing member, means for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retaining the connecting means in selected position corresponding to the tilted position desired, and a plurality of harrow spring teeth rigid with each shaft, each shaft including a plurality of teeth between the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts being offset a division of said spacing equal to the reciprocal of the number of shafts for tooth staggering, and a spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as between the other teeth thereon, the spacing between adjacent frames being the same as the spacing between the teeth on the same shaft.

'7. A spring tooth harrow structure including an elongated transverse towing member, means for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retaining the connecting means in selected position corresponding to the tilted position desired, and a plurality of harrow spring teeth rigid with each shaft, each shaft including a plurality of teeth between the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts being oifset for tooth staggering, and a spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as between the other teeth thereon, successive shafts projecting oppositely from the frame, the spacing between adjacent frames being the same as the spacing between the teeth on the same shaft.

8. A spring tooth harrow structure including an elongated transverse towing member, means for towing same and a plurality of spring tooth harrow units, each including a rectangular open end sled type frame pivotally connected at each forward corner to the member for linear towing of the frame, a plurality of tooth supporting shafts pivotally supported by the frame, each of two of said shafts projecting laterally beyond the same, means connecting all of said shafts for simultaneous tilting movement, means retaining the connecting means in selected position corresponding to the tilted position desired, and a plurality of harrow spring teeth rigid with each shaft, each shaft including a plurality of teeth between the runners of the frame and spaced apart substantially equidistant, teeth on successive shafts being offset, a division of said spacing equal to the reciprocal of the number of shafts for tooth staggering, and a spring tooth on each projecting shaft end spaced from the next adjacent tooth on the shaft the same distance as between the other teeth thereon, successive shafts projecting oppositely from the frame, the spacing between adjacent frames being the same as the spacing between the teeth on the same shaft.

9. In a gang type agricultural implement, the combination with a plurality of identical ground working units, each including a U-shaped frame member, a towing member, anchorages on the towing member spaced apart a suitable distance, and link means between each anchorage and the adjacent corner of the adjacent frame, one end having a permanent pivotal connection with the adjacent member, and the other end having a readily detachable pivotal connection with the other adjacent member, said readily detachable pivotal connection including a pin having a head spaced from the supporting member, said head having a reduced portion, and the link means including a slot for detachably receiving the reduced head portion of the pin in one position and retaining the connection in all other and the normal tractive position.

10. In a gang type agricultural implement, the combination with a plurality of identical ground working units, each including a U-shaped frame member, a towing member, anchorages on the towing member spaced apart a suitabe distance and link means between each anchorage and the adjacent corner of the adjacent frame, said link means having end connections substantially transverse to each other, each end being pivotally connected to the adjacent member for universal movement connection between members, one end having a permanent pivotal connection with the adjacent member, and the other end having a readily detachable complete pivotal connection with the other adjacent member.

1l. In a gang type agricultural implement, the combination with a plurality of identical ground working units, each including a U-shaped frame 0f member, a towing member, anchorages on the towing member spaced apart a suitable distance, and link means between each anchorage and the adjacent corner of the adjacent frame, said link means having end connections substantially transverse to each other, each end being pivotally connected to the adjacent member for universal movement connection between members, one end having a permanent pivotal connection with the adjacent member, and the other end having a readily detachable pivotal connection with the other adjacent member, said readily detachable pivotal connection including a pin having a head spaced from the supporting member, said head having a reduced portion, and the link means including a slot for detachably receiving the reduced head portion of the pin in one position and retaining the connection in all other and the normal tractive position.

12. A spring tooth harrow structure including a unit having a U-shaped frame, a plurality of shafts transverse to the arms thereof, one shaft being positioned near the rearward end of the frame and other equidistant spaced shafts positioned forwardly thereof, said last mentioned shafts alternately projecting oppositely beyond the frame, harrow spring teeth on the rearward shaft in alignment with the frame arms, and harrow spring teeth on the frame projecting ends of the other shafts.

13. A device as defined by claim l2, characterized by the addition of a spring harrow tooth on each of said shafts and positioned between the arm supported portions of the shaft.

14. A device as defined by claim 12, characterized by the addition of a harrow spring tooth on each of said shafts, the additional tooth on the rearmost shaft being positioned medianly between the arms and the additional tooth on each of the other shafts being positioned between the arms and adjacent the arm remote from the projecting shaft portion and in predetermined spaced relation to said remote arm and said medianly positioned tooth.

JOHN I. HOKE. 

